Release Planning: v7.5.4

[sirosen]

This is a planning space for the next pip-tools version. It may be retitled if we decide that the next version is a minor or major bump.

v7.5.3 is done, time to start looking forwards!

We have a new milestone up: v7.5.4

Of the items planned, these two are the ones I'm going to try to push forward on:

• [regression][6.10.0] pip-compile hangs on named pipes as input due to double-read #2232
• Introduce an initial LLM Usage Policy #2318

I also intend to look at old/stale PRs to see if we can close some of those up.